POLICE were called at 9.45pm on Saturday, January 31 with reports of a robbery at the Co-op store at Gardner Avenue in Corringham.
Two teenage boys forced a staff member to hand over the till by striking a member of the public with a hammer, causing minor head injuries. The boys then ran off in the direction of Southend Road.
Officers executed an area search for the suspects and the helicopter and dog unit were dispatched to assist but found no trace.
Enquiries continue to locate the suspects who are described as wearing dark tracksuits with their faces covered. One is described as black, of slim build and tall.
The other is white.
Police are linking the robbery with a similar incident which happened at 7.45pm at Post Office at Hathaway Road in Grays. A black man, believed to be in his early 20s threatened staff with a hammer before running off in the direction of Wallace Road, empty-handed.
The suspect was described as around 6 ft tall, wearing dark clothing and a scarf covering his face.
Anyone with information is asked to contact Essex Police on 101.